1. Field of the Invention
The present invention relates to a light source unit, an optical conversion unit, a light source apparatus, and a light source system.
2. Description of the Related Art
U.S. Patent Application No. 2006/0152926 proposes a light emitting apparatus with a combination of a first unit with a second unit. In this case, the first unit uses a blue laser light source and a light guide to guides laser light emitted by the blue laser light source and also uses a wavelength conversion member provided at a distal end of the light guide to convert the wavelength of the laser light. The second unit uses a laser light source for a wavelength shorter than the wavelength of blue light, a light guide, and a wavelength conversion member. U.S. Patent Application No. 2006/0152926 discloses that the combination of the first unit with the second unit improves a color rendering index compared to the first unit alone.
In recent years, for observation light source apparatuses such as endoscopes, much effort have been made to improve the visibility of an observation target by appropriately selecting a brightness level, a peak wavelength, a luminescent color, that is, a spectral shape, a radiation angle, and the like according to the purpose of the observation.
In connection with such effort, to obtain light that meets the purpose, the light source apparatus in U.S. Patent Application No. 2006/0152926 needs preparation of units each using a laser light source, a light guide, and a wavelength conversion member and the number of which is equal to the number of types of light needed for the purpose. However, preparing a large number of units is difficult in a practical sense in terms of costs, a storage site, and the like.